Patent-treuhand-gesellschaft F. Elektrische Gluehlampen Mbh

Teja Lehmann

Michael Boenigk

Klaus Guenther

Hans-Georg Kloss

To provide for optimum control of a sodium high-pressure discharge lamp operating under saturated operating conditions, such that the lamp will be operating stably and providing light output which is an optimum with respect to the color rendition index (Ra), light output or luminous flux, and color temperature, without regard to manufacturing tolerances or variations in power supply voltage, the energy supplied to the lamp is controlled with respect to a quotient formed of lamp voltage and lamp current (V.sub.L /I.sub.L), said quotient being determined with respect to optimum light values. The power supply for the lamp (3) either is a stabilized output voltage power supply (22) in which the output current is controlled, or an oscillator (32) providing bursts or power pulses (10, 10') formed of oscillations (11). Both the number of power pulses as well as holding pulses (12) between power pulses (to prevent extinction of the lamp), energy level of the respective pulses and frequency of oscillations, respectively, can be controlled to obtain the optimum value for the quotient of lamp voltage and lamp current.

Growing community of inventors

Berlin, Germany

Teja Lehmann